icons.css

/* Icons */
.icon-collapse,
.icon-expand {
  background-image: url(img/icon-collapse-expand.png);
  background-position: left top;
  background-repeat: no-repeat;
  width: 14px;
  height: 14px;
  margin-right: 1em;
}
.icon-expand {
  background-position: left -14px;
  margin-top: -1px;
}